Basically I’m wondering if です can be nominalized.
For example how would you say:
”I don’t like being mean.” or
”It’s good to be nice!”
Can I say:
酷いであるのが好きじゃない?
優しいであるのがいい?
These are my attempts but I don’t feel confident in these!
i-adjective + である is not grammatical for the same reason i-adjective + だ is not grammatical: i-adjectives already serve as a predicate without need for a copula (or in other words, you can imagine that the meaning “is”/“to be” is embedded in the i-adjective). i-adjective + です is grammatical, but the です here is not the usual copula, it is just a polite marker which serves no purpose but to make the i-adjective polite — you can tell the difference because it never conjugated (i.e., 優しいでした and such is incorrect).
Unfortunately this reality makes the phrasing of your question very hard to respond to because it’s unclear if you’re asking “how to nominalize です (politeness)” or “how to nominalize i-adjectives”.
The former is easy to answer: you don’t, because you generally don’t have politeness in relative clauses.
The latter is more complicated.
Since an i-adjective is a predicate, you can stick it right next to the の:
優しいのが好き
“I like kind things”
But as you can see it doesn’t have the intended meaning.
To get the intended meaning you need to use 優しくする:
優しくするのが好き
“I like being nice to people”
Aside for Advanced Learners
Unfortunately this is all a little oversimplified and “優しいのが好き” can, depending on what subject you consider is omitted or what context is available, also mean other things like
“I like the fact that he is kind”
「(彼が)優しいのが好き」“I like when someones interaction style is kind” (=“I like when people are kind to me”)
「優しいの(=接し方)が好き」(And most confusingly, this last imagined context can also lead to it meaning “I like being nice to people”, but only with the right context, which is why it is not the default go-to phrase when you are trying to say this.)
But it’s hard to all explain at once. Hope this helps!
Yes, です can be nominalised in the form である by attaching こと. However, as pointed out by previous answers and comments here, this is not the case with the です you present in your example sentences which is marking the sentence as polite.
You can say であること to nominalise a clause in certain grammar patterns such as Aことが分かる, where A is a noun or a na-adjective sentence you would normally end with です:
東京は安全です。 Tokyo is safe.
このレポートを読むと、東京は安全であることが分かります。You can realise Tokio is safe by reading that report.
For sure there may be other patterns where this nominalisation であること takes place.
Basically I’m wondering if です can be nominalized.
です is not the dictionary form.
Dictionary form for です is だ.
So, your question should be asked as:
Can だ be nominalised?
Nominalisation (or to nominalise) litteraly means [to make a noun].
So, if to say your question in simple words, than it would turn to:
Can I make a noun from だ?
If to look at how だ is used everywhere it is easy to notice, that だ is always used with some other word and never alone. Therefore, there is just no need to make a noun from だ, cause it always make sense to use the word, which was used with だ, than to use だ itself.
I don't have a right to give any advices on Japanese usage, but if I have to find solution for your case, I would split your sentances into 2 parts like this.
When I am a mean person, I don't like this.
When I am a mean person, I feel bad about it.
When I am a nice person, I like this.
When I am a nice person, I feel good about it.
Maybe this stratagy is stupid, but I believe it is better, than to search for word-to-word translation from other language to Japanese.